Early outcome prediction (NEWS, EWSO2 and HRV) for spontaneously breathing ICU patients - A data-warehousing analysis

Abstract

Abstract Purpose Predicting models using physiological parameters have been developed for use in the emergency department. The aim of our study was to evaluate NEWS (New Early Warning Score), EWSO2 (Early Warning Score Oxygen), and Heart rate variability (HRV) as outcome predictors for spontaneously breathing patients attending the ICU. Methods A post-hoc analysis of a prospective datawarehousing project (ReaSTOC clinicalTrials identifier NCT 02893462). Physiological data and raw PPG curves were prospectively collected during the first 24-hrs of ICU admission. NEWS, EWSO2 and HRV were calculated and the best thresholds to predict the need for invasive ventilation and mortality were determined. Results From 112 patients, 8 and 18 patients died within the ICU and during their hospitalization respectively. Patients who died in ICU had a highest NEWS score as compared to ICU survivors (9,0 [5,0–11,6] vs. 6,0 [5,0–7,0]; p = 0.03), highest EWSO2 index (18,4 [15, 7–19, 8] vs. 9,0 [5, 8–20, 9], p = 0.008). Considering a composite prognostic outcome including ICU mortality and/or the need of invasive ventilation and/or a length of stay superior to the median length of stay of patients without invasive ventilation, there was also a significantly difference for NEWS, HRV and EWSO2. Conclusion For spontaneously breathing patients attending the ICU, NEWS, EWSO2 and HRV were significantly different in between ICU and hospital survivors and non-survivors. These parameters also enabled an early detection of subsequent additional respiratory assistance (e.g high flow oxygen, noninvasive ventilation) but not the requirement for endotracheal intubation.